Means for attaching pole-pieces.



No. 792,607. I PATENTED JUNE 20, 1905. J. F. McELROY.

MEANS FOR ATTACHING POLE PIECES.

APPLICATION FILED IAB. so, 1905.

lnlflnesses Invenlfi? z 1 (MM E I fwfig UNITED STATES Patented June 20, 1905.

PATENT OFFICE.

JAh IES F. h ioELROY, OF ALBANY, NEW YORK, ASSIGNOR TO CONSOLI- DATED OAR HEATING COMPANY, OF ALBANY, NEIV YORK, A COR- PORATION OF \VEST VIRGINIA.

MEANS FOR ATTACHING POLE-PIECES.

SPECIFICATION forming part of Letters Patent No. 792,6(17, dated June 20, 1905.

Application filed March 30,1905. Serial No. 252,980.

To (fl/N whom, it may concern:

Be it known that I,JAMEs F. McELRoY,a citizen of the United States, residing at Albany, county of Albany, State of New York, have invented certain new and useful Improvements in Means for Attaching Pole-Pieces, of which the following specification and accompanying drawings illustrate one form of the invention which I now regard as the best out of the vari ous forms in which the invention may be embodied.

This invention relates to a means for securing laminated magnet-pole pieces to their seats or yokes. Its principal objects are increased strength and simplicity.

Of the accompanying drawings, Figure 1 represents a perspective view of an embodiment of the invention, partly in section. Fig. 2 represents a radial section transverse to the planes of the disks. Fig. 3 represents an elevation of the bolt looking endwise of its head p0rti0n.

In the drawings, 1 is the magnet-yoke or attaching-base, and 2 is the pole-piece or magnet-core made up in a well-known manner of a large number of separate sheets or laminae 3 3.

4 4 are the attaching-bolts, of which I have shown two for each pole-piece, each bolt being T-shaped and composed of a head or key portion 5 and a stem portion 6, integral with and projecting at right angles to the head portion. This stein projects suiliciently beyond the seating-face of the pole-piece to traverse the yoke 1 and is formed with a screw-thread 7, engaged by a nut 8 on the outside of the yoke, whereby the pole-piece is clamped to the yoke.

Preferably each pole-piece is provided with three holes transverse to the laminae, which holes may be made in the laminae when the latter are punched out. Two of these holes are occupied by rivet-bars 9 9, upset on their ends for holding together the laminae as a unit or group. I have also shown malleable-iron cheek-plates 1O 10 with rounded edges for the terminal plates of the group. A third transverse aperture in the pole-piece receives the cross-bars, heads, or key portions 5 of the bolts. In addition to the transverse holes there are formed in the pole-piece from its seating-face holes parallel to the planes of the laminae for receiving the stems 6 of the bolts.

After the lamime have been assembled as a unit the holes for the stems 6 may be bored. The laminae are then separated in the middle of the stem-holes, the bolts at inserted, and the laminae reassembled, or the bolts may be inserted as the liminae are piled together and the rivets 9 then inserted and upset on their ends to secure the whole together. The polepiece is then complete ready for attachment, and it is observable that the bolts cannot be removed without separating the laminae. The bolt-stems cannot be lost, and they serve as dowels to position the pole-piece on its seat when applied thereto.

Greater strength is attained by this method of attachment than by a method which involves screw-holes or other openings in the part which traverses the laminae. The bolts are drop-forged, and at the juncture between stem and head they have the full strength due to the cross -section of metal at that point, which would not be true, for example, of a cross-piece bored to receive a threaded stem or bolt. The cross -piece may also be of smaller dimensions than in the prior arrangement just mentioned.

\Vhatl claim as new, and desire to secure by Letters Patent, is-

1. The combination with a pole-piece made up of separate laminae, of an attaching-bolt having a key portion confined in the laminae and a stem portion at an angle to and integral with the key portion.

2. The combination with a pole-piece made up of separable laminae, of an attaching-bolt having a head embedded in the laminae transverse to the planes thereof, and a stem integral therewith, projecting beyond the polepiece longitudinally of the planes of the laminae and formed with attaching means on its projecting portion.

3. The combination with a pole-piece made up of separable laminae, of a T -shaped onepiece bolt whose head occupies a transverse close-fitting aperture in the pole-piece and its stem, a longitudinal aperture therein, and means engaging a projecting end of the stem for securing the pole-piece to a yoke.

4:. The combination with a magnet-yoke, of

. a laminated pole-piece, an attaching-bolt having its stem embedded between the laminae of the pole-piece, a key portion integral with the stem and engaging the laminae, anda projecting portion on the stem traversing the yoke and screw-threaded, and a nut engaging the screw-thread for securing the bolt and pole-piece to the yoke.

JAMES F. MoELRoY.

-Witnesses:

WILLIAM A. MORRILL, J r., ERNEST D. JANSEN. 

